A paper co-authored by a Sussex academic has won the Best Paper Award at an international conference on the simulation and synthesis of living systems.

One of the theories about the origin of life-like processes involves "autocatalytic cycles": groups of chemicals that collectively participate in a behaviour analogous to self-reproduction.

The prize-winning paper, Self-Organising Autocatalysis (by Dr Nathaniel Virgo, Dr Simon McGregor and Professor Takashi Ikegami) uses an elegant abstract simulation model to illustrate how autocatalysis can be inevitable when the right conditions of energy imbalance are in place.

The model simplifies real-world chemistry by assuming that molecules are made up from just one type of building block and have no internal structure. This ignores the differences between real-world chemical elements, but reflects the principle that matter cannot be created or destroyed in chemical reactions. It turns out that, even in such a simple model, groups of chemicals will self-organise to produce a runaway growth process, like rabbits multiplying, providing that enough "food" is fed into the system. The simplicity of the model allowed the researchers to prove their result mathematically, as well as to demonstrate it in simulation.

"Our model manages to be simultaneously simpler and more realistic than most other artificial chemistries," says Dr McGregor. "Previous research made the wrong sorts of abstractions: it turns out that as long as you take energy flow seriously, catalysis and autocatalysis just emerge from cycles of ordinary reactions, much as they do in physics. We've shown yet again that when you study complex phenomena, it pays to keep it simple."

Dr Virgo and Dr McGregor both conducted PhDs and postdoctoral research in the Department of Informatics at the University of Sussex. Dr Virgo is now at the University of Tokyo, as is third author Professor Ikegami, while Dr McGregor is a Tutorial Fellow at Sussex.